<HTML><HEAD><TITLE>event_retrieve(+EventHandle, -Goal)</TITLE>
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<H1>event_retrieve(+EventHandle, -Goal)</H1>
Given the handle with which an event is associated, retrieve the event goal.
<DL>
<DT><EM>EventHandle</EM></DT>
<DD>An event handle
</DD>
<DT><EM>Goal</EM></DT>
<DD>A free variable or goal to unify
</DD>
</DL>
<H3>This built-in predicate is obsolete!</H3>
<H2>Description</H2>
	The goal associated with an event handle, created using event_create / 3, is
	retrieved using this predicate.
    <P>
	Like event creation, retrieval of the goal produces a copy of the
	goal. As a result, if the goal contains variables, they lose their identity 
	and are replaced with fresh ones.
    <P>
        If the event was disabled, the goal 'true' is retrieved instead of the
	original goal.
    
<H3>Modes and Determinism</H3><UL>
<LI>event_retrieve(+, -) is det
</UL>
<H3>Exceptions</H3>
<DL>
<DT><EM>(4) instantiation fault </EM>
<DD>EventHandle is un-instantiated
<DT><EM>(5) type error </EM>
<DD>EventHandle is not a handle
</DL>
<H2>Examples</H2>
<PRE>    ?- event_create(writeln('Hello world!'), [], Event), event_retrieve(Event, EventGoal).

	Event = 'EVENT'(16'50421bd0)
	EventGoal = writeln('Hello world!')
	Yes (0.00s cpu)
    </PRE>
<H2>See Also</H2>
<A HREF="../../kernel/event/event_retrieve-3.html">event_retrieve / 3</A>
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